As turf wars carry on among the BMW 3 Series, Audi A4 and Mercedes C-Class, the all-new Cadillac ATS elbows its way in with lightweight construction, agile handling and a beautifully executed interior. And while it may not rule the roost, the Cadillac ATS is definitely in the game.

The 2013 Cadillac ATS was designed and engineered from the ground-up on an all-new platform. Its compact size marks a turning point for Cadillac, which has bought into the same sausage, different lengths philosophy of the Germans and now has true compact, midsize and full-size sedans in its lineup. ATS is the luxury brand's small offering (well, as small as compact can get these days, considering they're all getting bigger), and while it may not be diminutive, it's one of the leanest of the pack thanks to weight-saving technology, including the use of lightweight metals, that whittles the ATS curb weight down to as low as 3,315 pounds on base models, less than comparably equipped German competitors.

As with most cars in this class, the Cadillac ATS uses rear-wheel drive. All-wheel drive is available on some models.

Three engine choices are available on the 2013 Cadillac ATS, including two all-new four-cylinder options. Each uses direct injection and variable valve timing to maximize performance and fuel efficiency. The base engine is a 2.5-liter naturally aspirated inline-4, good for 202 horsepower and 191 pound-feet of torque. It's the least expensive and slowest of the bunch, with a manufacturer estimated 0-60 mph time of 7.5 seconds. A sprightly 2.0-liter turbo makes 272 hp and 260 lb-ft of torque and can go 0-60 mph in an estimated 5.7 seconds with the automatic transmission, or 5.8 seconds with the available manual. The top-of-the-line powertrain is GM's much-used 3.6-liter naturally aspirated V6, good in this application for 321 hp and 275 lb-ft. of torque, which propels the ATS from 0-60 mph in just 5.4 seconds. All versions of the ATS use GM's 6-speed Hyrdomatic transmission, with the exception of the 2.0-liter turbo, which also offers a new 6-speed manual in some trim levels.

Like its big brother the CTS, the Cadillac ATS was tuned on the track, including Germany's famous Nurburgring, often used by European car companies during the development process. The result is a light but solid chassis with near 50/50 weight distribution (a la BMW) that performs beautifully on the road. Driving dynamics are further enhanced by an all-new five-link independent rear suspension and optional Brembo brakes with an all-new, high-tech coating that keeps the rotors looking as good as they perform. Magnetic Ride Control, now in its third iteration, is optional on most ATS models, which adjust suspension real-time for even more responsive driving.

Inside, fit and finish rivals that of any Audi or BMW, although we found some interior configuration options limiting. Upper trim levels of the ATS use CUE, Cadillac's new touchscreen interface. An acronym for Cadillac User Experience, the large screen uses proximity sensors, haptic feedback and voice recognition to control phone, audio and navigation functions. Unlike many luxury vehicles with proprietary interfaces (like the BMW iDrive and Mercedes Benz's COMAND system), there is no central control knob on the center console and all functions are performed either through voice or via the touchscreen. However, CUE doesn't appear on the base model, and navigation costs extra on all but the most expensive trim levels.

Fuel economy for the Cadillac ATS 2.5-liter model with rear-wheel drive is an EPA-estimated 22/33 mpg City/Highway and, unlike its German rivals, Regular gasoline is recommended. The ATS with 3.6-liter V6 is rated at 19/28 mpg, also on Regular gas, or 18/26 mpg with all-wheel drive. ATS 2.0-liter turbo automatic is expected to be 22/32 mpg.

In addition to the BMW 3 Series, Audi A4/A5, and Mercedes-Benz C-Class, the ATS competes with the Acura TSX and Lexus IS.

Walk Around

Exterior styling on the ATS is bold, continuing Cadillac's Art and Science design language that's been in use for a decade. The design stems from early sketches that came out of GM's London studio, with the bulk of the exterior and interior refined and finished by designers from both the Michigan and California studios. The ATS will be built at GM's Lansing Grand River Assembly Plant in Michigan.

Lines are cleaner and certain features are less over the top than those on other cars in this class and are more proportionate to (and appropriate for) its smaller size. But the ATS is still unmistakably a Cadillac, which will please brand loyalists and appeal to those who are looking for something unique in a sea of sameness, but may prove a tough sell for European-luxury car enthusiasts who prefer sultry swoops to Caddy's sharp geometric shapes.

Headlamps on the ATS use Cadillac's signature vertical shape, with long, tapering tails that stretch up alongside the hood line. Vertical foglamps underneath accentuate the upright look of the front fascia. The front grille and air intakes are large, but not gratuitous, and are separated, in Cadillac style, by a sharp, three-dimensional angular crease. The front end is not only aesthetic, but functional: Inside the front grille are shutters that automatically close at certain highway speeds to reduce aerodynamic drag and help fuel economy.

From the side, the ATS appears squared-off, but not as wedge-y as the CTS. A rising character line along the bottom is evident, but not overdone. The roofline slopes gently past the C-pillar, and isn't as steeply raked as some sporty compact cars, presumably for the sake of rear passenger headroom. Chrome accents on window surrounds and door handles, as well as polished 17-inch wheels (with optional 18s), convey a look that's more luxurious over sporty. In addition, the Brembo performance brakes that come on some ATS models use a special Ferritic Nitro-Carburizing (FNC) coating, which helps to prevent corrosion and keeps them looking shiny.

In back, the vertical lines are repeated in the tail lamps. A long, thin horizontal LED brake doubles as a rear spoiler. The license plate is framed in shapes that would make Euclid (the father of geometry) proud. The rear bumper echoes the front with its sharp center crease.

Interior

As with other Cadillac interiors, materials on the ATS are high-quality and luxurious. Front seats make driver and passenger feel like each is in her own compartment, flanked by an armrest at one hand, and a high center console on the other. The interior design echoes the lines and shapes of the outside, with sharp angles and rising lines that wrap around and create a seamless flow from the center instrument panel to the doors.

The ATS features extra touches like handcrafted cut-and-sewn leather upholstery on upper trim levels. A number of interior color and trim packages are available, but we weren't crazy about some of the options. Aluminum trim inserts, for example, sport etched rectangular patterns evocative of a 1980s Duran Duran album. And while we liked a different model's red-flecked carbon fiber accents on doors and vent surrounds, we were disappointed to learn they were only available as a package with red leather upholstery. A Cadillac exec told us we could order the carbon fiber inserts separately, but we'd have to change them out ourselves (and perhaps try to recoup our losses by selling the original trim on eBay).

Base versions of the ATS include a 4.2-inch color information display, which we weren't able to see in person, presumably because Cadillac is pushing its new CUE system, a voice-activated proprietary interface with an iPad-like 8-inch touchscreen. While past Cadillac models were fraught with an overwhelming number of buttons on the center stack, CUE drastically cuts down the number of controls to just a handful. It controls audio and telephone functions, as well as directions and map information on cars equipped with navigation.

CUE's home menu is configurable so you can access your favorite functions easily. It also uses proximity sensing, which saves extra steps and keeps your attention better focused on the road. When driving, CUE will display full-screen maps or audio information, but when your hand is nearby, it automatically brings up menu options related to the current function on the screen.

We were pleasantly surprised by the navigation and voice activation. Voice recognition systems can be painfully inaccurate (just ask anyone with the latest iPhone), but CUE's is no short of impressive. It understands natural voice commands, meaning you don't need to use pre-canned terms to get it to do something. Even better, it can correctly identify difficult names from an address book, although it will most likely butcher the pronunciation when repeating it back to you.

While CUE is mostly user friendly, there are still a few oddities. One of these is that it uses physical buttons on the center stack, located below the screen for the climate control's fan speed and temperature. However, if you want to change vent mode, you have to go in to the CUE menu. Another thing that annoyed us was the barrage of fingerprints that appeared on the screen after just a few minutes of use. The ATS does come with a microfiber cleaning cloth, but it's not an elegant solution.

Front seats are comfortable, and offer a good range of adjustability from petite to tall. Because it's a smaller, sporty car, bolsters hug driver and front passenger tighter than in other Cadillac models, which is a good thing when navigating winding roads. On cars equipped with the optional Driver Awareness Package, the driver's seat will vibrate when the lane departure warning or forward collision alert is activated. If a vibrating seat isn't your style, you can change the warning to an audible tone. As for us, we think the vibrators should have a manual on/off switch and be repurposed as seat massagers.

In back, legroom is on the tight side, but comparable for a car of this class. It offers about the same as the Mercedes-Benz C-Class, but about an inch and a half less than the Audi A4 and BMW 3 Series sedan. It's a similar story with rear headroom; the ATS is comparable to the Mercedes, but falls about an inch short when compared to the Audi and BMW. This is especially curious considering the overall length of the ATS is two inches longer than the C-Class, and practically three inches longer than the A4.

Trunk space in the ATS falls short of that of the Audi A4 and Mercedes C250, which offer 12.4 cubic feet of cargo space, and the BMW 328i, which offers a roomy 13 cubic feet.

Driving Impressions

The Cadillac ATS architecture is all-new, built from the ground up. It uses a combination of several metals, including high-strength steel, aluminum, magnesium, and many others that together help achieve rigidity and lightness, while still keeping attainable pricing. The result is a solid, stable chassis that is wonderfully compliant on the road as well as on the track, with a hunkered-down feel and little-to-zero body roll. The near-50/50 weight distribution keeps the car feeling balanced and controllable around all twists and turns.

We drove the 2.5-liter Luxury ATS on the street, and while it was perfectly adequate for freeway cruising and tooling around town, we much prefer the 2.0-liter turbocharged four-cylinder, which Cadillac expects will account for the majority of ATS models on the road. With its twin-scroll design, torque is readily available on the low end, with a smooth power band an imperceptible lag (although, for fuel economy reasons, you can't get a wide-open throttle right off the line anymore, on any car). Passing was easy, and we never felt short of power, except perhaps a tad around sweeping turns up steep inclines.

The cabin of the ATS is very quiet. We noticed very little road or wind noise while driving. Even the direct-injection engines, which are notorious for their clickety-clackety ticks, couldn't be heard much in the cabin, thanks to plentiful and well-placed sound insulation.

The 6-speed manual transmission was mostly a joy to drive, although we occasionally found ourselves rowing between third and fourth on demanding roads, frustrated that the latter was too tall and the former was strained and noisy. We found the same issue on ATS models equipped with the 6-speed automatic, a gap in the ratios between third and fourth gears. Still, we applaud Cadillac for offering a manual option in a world where others seem to be going the way entirely of paddle shifters.

On the track, we found the 2.0-liter turbo engine had plenty of power to make it fun, but not quite enough to make it effortless. And for those who actually like to work for a lap time, that's a good thing. The 3.6-liter V6 with Magnetic Ride Control, however, was another story. The favorable power-to-weight ratio with the V6 in the ATS makes for a dynamite ride. After a few laps in the ATS V6, it's impossible not to dive into the pit lane smiling.

On both models, the Brembo performance brakes stopped quickly and efficiently.

We have mixed feelings about the new ZF-sourced variable-effort electric steering. Nearly everyone is going to electric steering now, much to the chagrin of some die-hard enthusiasts. The steering gear used in the ATS is belt driven, which Cadillac claims makes for a smoother feel, but we found it a little numb on demanding racetrack turns. Still, we think most drivers will find it satisfyingly responsive in a range of driving situations.

The EPA gives the ATS 2.5-liter model with rear-wheel drive a fuel economy rating of 22/33 mpg City/Highway. Estimates for the 2.0-liter turbo with the automatic transmission are 22/32 mpg City/Highway. The 3.6-liter V6 is rated 19/28 mpg City/Highway; ATS AWD automatic is rated 18/26 mpg. The V6, if properly equipped, can run up to 85 percent ethanol, but E85 fuel gets a dismal 14/21 mpg rating and the EPA estimates it will add $600 to your annual fuel bill.

The 2013 Cadillac ATS is a well-executed compact luxury sports sedan with performance that keeps up with the best from Germany. Sporting rear-wheel drive and a rigid chassis, it's quiet, fun and easy to drive fast. A range of power trains offers a wide range of price, performance, and economy.

Laura Burstein filed this NewCarTestDrive.com report after her test drive of the Cadillac ATS models near Atlanta.